Safety device



S. SHOLD.

S'AFETY DEVICE. APPLICATION FILED ocr. 22. I921.

1 ,%3@,4L-1 Go PatentedSept. 26, 11922.

Patented Sept. 26, 1922.

NITED STATES SIEGFRIED SHOLD, OF MANSFIELD, OHIO.

, SAFETY DEVICE.

Application filed October 22, 1921. Serial No. 509,554.

T 0 all whom it may concern:

Be it known that I, SIEGFRIED Snow, a subject of Sweden, residin at Mansfield, in the county of Richlan and State of Ohio, have invented certain new and useful Improvements in Safet Devices, of WhlCll the following is a speci cation.

This invention relates to a safety device for use on machines provided with cooperating pressure elements such as punching presses and the like.

The primary object of the invention is to provide means of swingmg a safety device between the cooperating pressure elements simultaneously with, or just after the commencement of a stroke of one element toward the other or the strokes of both toward each other, thereby providing means for shoving or pushing the hand (or any part of the anatomy of the operator) from the danger zone between the elements after the operator feeds the work between the pressure elements and prior to the time that the movable-pressure elements or elements reach a relative position (or positions) with respect to each other that is, likely to result in injury to the operator.

Another object of the invention is to construct and operate a safety device that is adapted for automatically removing work from between the pressure elements, when part of the work is pressed to a higher or lower plane from the body portion of the work, the work being removed from between the elements by the return stroke of the safety device, thereby adding efficiency in the operation of the machine increasing the quantity of the output of the machine by saving time and labor that would be consumed by the operator in removing the work from between the pressure elements after being acted upon by the element.

A further object of the invention is to construct a safety device that is applicable to be used in cooperating with machines equipped with pressure elements which safety device is automatically operable for safety purposes when the machine. is actuated intentionally by the operator, or when actuated without any act upon the part of the operator.

Further objects of invention consists in providing means for the vertical adjustment of the safety device, for chan ing the relative position of the safety device at the end of its travel in either direction with respect to the pressure elements or dies and to vary or chan e the distance of the throw of the safety ev 1ce to provide for swinging the safety device over or beyond, different sizes of ressure elements, dies or the like.

hese and other objects are attained by the mechanism ilu strated in the accompanymg drawing in whic Y Tfig. l, is a side elevation of a part of the mechan sm of a conventional type of punching ress, showing the safety device applied to t e press. and in a position about to be swung or moved between the pressure elements.

Fig. 2, is a side elevation of a part of a punching press showing the invention apphed thereto and in a position, preparatory to being swung or moved between the pressure elements upon its return stroke to its normal position,

Fig. 3, is a front elevation of a part of a punching press showing the invention applied thereto.

Fig. 4, is an enlarged plan View, of the pivoted yoke supporting bracket takenon the line 1-1 of Fig. 1.

The type of press shown is a conventional type of punching press which is operated by a treadle mechanism, (not shown). The treadle mechanism is operated to impart a reciprocating movement to a rotatable shaft and one of the pressure elements of the press (or both) periodicallyor continuously through the medium of movable connecting mechanism which operate a clutch at the will of the operator. The treadle mecha- I11SI1'1 is not shown as it forms no part of the present invention.

The operation of the safety device is not dependent upon the treadle mechanism for its operation. The safety device will operate to perform its function by the eccentric shaft of the press when the shaft is rotated, by any power means.

In the drawings the invention is shown applied to a punching press asaconventional means of showing and describing its operation and functions. It will be apparent to those skilled in the art that the safety device can be applied without material alteration or change to machines of different types which are equipped with pressure elements and a rotating eccentric shaft without departing from the principle of the invention.

In the preferred application of the safety Y devlce to a punching press or the like as a heretofore set out, the frame of the press is represented by reference numeral 1. An eccentric shaft 2 is journaled in the usual manner in the frame and a flywheel 3 is loosely journaled on said eccentric shaft and it cooperates with a clutch mechanism (not shown) to impart a rotating movement to the eccentric shaft 2 to periodically or continuously to actuate the movable element or elements connected thereto to perform the work at the will of the operator by the actuation of an ordinary pedal mechanism of a press.

A reciprocating head or pressure element 4 is connected to the eccentric portion of the shaft 2.and is adapted to move or reciprocate the movable pressure element to and from the pressure element 5.

The parts he-reinbefore described are common in the construction of the type of punching press shown in the drawing and do not form any part of the present invention, except in their cooperative relation to the parts or elements which will now be described.

The shaft 2 as shown has its ends reduced at 6 to provide shoulder portions between the frame members to prevent endwise movement of the shaft. The reduced por tion 6 of the conventional type of eccentric shaft 2 is also provided with a key-way 7.

In the application of the invention to the type of press referred to a combined cam 8 and sector 9 is provided and mounted upon the reduced portion of the shaft 6 and held rigidly in place by a key 10 which is fitted to the key-way 7 formed in the reduced portion 6 of the shaft and a corresponding keyway formed in the sector 9. It may be also held in place by the set screw 9'.

A yoke shaped supporting bracket 11 is pivoted at a pre-determined point to the frame 1 of the press upon a bolt 12 which is threadably attached to the frame of the press. A. shouldered spacer 13 is mounted upon the bolt 12 between the arms of the bracket 11. A pin 14 is journaled adjacent to the ends 15 and 16 of the arm of the pivoted yoke bracket and is held in place and prevented from endwise movement by cotter pins 17 and 18. v

The ends 19 and 20 of a link bracket 21 are pivotally connected to the pin 14 and a roller 22 is journaled upon the pin between the free ends 15 and 16 of the arms of the pivoted yoke shaped bracket 11. A bracket 23, is preferably secured to the press at a pre-determined vertical position with reference to the combined cam and sector by the bolts 24. The fixed bracket as shown is preferably formed cone shape.

A plate 25 of suitable form and dimensions is pivotally hung upon a pin 26 which is in turn secured to the bracket 23. One end of the plate 25 is pivotally connected by a pin 27 to the lower end of the link bracket 21. A safety device 28 comprising a swing-" pressure elements and swing over and beyond the danger zone, between the pressure elements.

A slot 31 is formed in the pivoted plate 25 and a bolt 32 is providedto pass through the pivoted ar1n28 and the slot 31 providing means to hold the part 29 in any adjusted position, so as to allow the parts 2829 and 30 to swing with respect to the pressure elements, to difierent positions relative thereto.

A series of apertures 33 are provided in the pivoted plate 25 to permit the pin 27 which connects the link bracket 21 to the plate, to be connected to the; plate at different points with respect to the fulcrum pin 26 of the plate, so as to provide means of varying or changing the distance of the throw of the part 30 of the safety device.

Referring to Fig. 1, reference numeral 31 represents a blank resting upon one of the pressure elements before the pressure elements have acted upon the blank or work. The part 30 of the safety device is adjusted so as to swing over the work or blank in close proximity thereto.

Reference numeral 35 represents a part of the blank pressed upward above the plane of the body portion of the blank or work permitting the part 30 to contact therewith on its return stroke and automatically eject, remove or kick off the pressed blank or work from between the pressure elements.

The operation of the invention in brief is as follows The part of the safety arm 30 is vertically adjusted through the medium of slots 36 formed in the parts 28 and 29 and the bolt 37 is tightened to hold the part in the adjusted position, so that the part 30 will swing in close proximity to the work or blank The throw of the part 30 isthen adjusted so as to carry it beyond both ends of the pressure elements or dies as shown in Figs. 1 and 2. If it is desired to throw the part 30 in different relative positions with respect to the pressure elements or die, the arm 28 is adjusted as desired and held in its adjusted position by the bolt 32 so that its strokes move the part 30 either further away from or closer to the front or rear of the pressure elements or die.

In the event of the use of pressure ele ments or the dies of different sizes the throw of the arm carrying the part 30 is adjusted to correspond with the size of the die or pressure element by changing the pin 27 from one aperture 33 and moving into a different aperture of the series formed in the pivotal plate 25. This adjustment gives *the re uired throw of the .part 30 to correspon and its connected mechanism in t e with the different sizes of dies and always maintain the part 30 in close proximity to the pressure element or dies irrespective of the size thereof.

An expansible spring .38 of any type is adapted to exert its pressure or tension to normally hold and retain the safet device positions shown in Fig. 1 and constantly forces the roller 22 in contact with the race of the cam 8. If the spring 38 should break, is removed, or out of repair the weight of the connecting parts of the safety device will swing the safety device carrying the part 30 by gravity to the position s own in Fig. 2 where it will remain until operated by the cam, to swing the part 30 between the pressure element preferably at the same time, as the movable pressure element starts on its down stroke.

The elements just described provlde for the mathematical adjustment of the parts to carry out purposes and objects described herein. When all of the described adjustments have been made and the eccentric shaft 2 is rotated in the direction of the arrow either intentionally or without any act upon the part of the operator, and the cam is rotated from its normal position as shown in Fig. 1 the cam exerts a pressure against the roller 22 forcing the safety mechanism to swing or move part 30 forward between the pressure elements until the part 30 reaches the position shown in Fig. 2 at which times the roller 22 reaches the critical point '39 where it merges w1th the sector 9, and part of the cam 30 and its connecting mechanism is then malntained or retained in the position shown in Fig. 2 by contact of the roller 22 with the sector, until the sector is rotated to the point indicated at 40 at the point where the sector merges with the cam allowing the roller to travel on low part of the cam, gradually permitting the art 30 of the arm to be drawn or pulled ack to its normal position (as shown in Fig. l) by the spring 38, swinging or moving the part 30 between the pressure elements.

In ad usting the safety device to perform its functions it is preferably adjusted, so that the part 30 of the safety device will start to swing between the pressure elements at the same time as the movable pressure element or elements starts on its or their stroke toward each other, (or the other) or immediately thereafter and the return stroke of the part 30 is timed to commence to swing or move between the pressure elements at or about the time the movable pressure element or elements have traveled about one half way or more upon its (or their) return stroke.

Attention is called to the fact that the throw of the arm can also be varied more or less by changing thesize of the combined sector and cam. The swinging speed of the arm carrying the part 30 will also be varied when the size of the combined sector cam is changed.

Attention is. further called to the fact that by changing the race of the sector, that the safety device can be maintained in idle position a pre-determined length of time and by changing the race of the cam the safety device can be actuated to swing at re-determined times.

claim:

1. In a safety device for machines having ac-operating pressure elements, a disk provlded with a cam face mounted for rotation on the frame of the machine, a mechanism comprising a connected link mechanism provided with an arm which is adapted when actuated by the cam to oscillate to and fro in the direction of theopera-tor between the co-operating pressure elements, said oscillating arm being adapted to be adjusted to' swing to different positions relative to the die and punch and being adjustably secured to the pivoted plate to change the throw of the oscillating arm.

2. In a safety device for machines having co-operating pressure elements, a rotary shaft journaled on the machine, a cam secured to the rotary shaft, a U shaped bracket pivotally mounted on the machine carrying a roller which roller is adapted to contact with said cam, a link pivoted to'said bracket, a second bracket secured to the frame beneath the aforementioned bracket and connected to, said link, a pivoted member secured to said bracket, an adjustable arm secured to the pivoted member which is adapted to oscillate between the pressure elements at pre-determined times when movement is imparted to the arm through the medium of the said cam.

3. In a safety device for punching presses, a rotary shaft, a cam mounted thereon, a cam actuated means comprising a pivoted bracket, a pivoted plate and an adjustable link connected to the plate, which mechanism is secured to the frame of the press and adapted to be actuated by the aforementioned cam to oscillate the arm of the cam actuated means at predetermined times to and fro between the pressure elements and adjustably maintain said arm at both ends of its throw free from, but adjacent to the pressure elements at the ends of its throw.

4., In a safety device for punching presses, a rotary shaft, a cam mounted thereon for lateral adjustment, a pivoted cam actuated means carryin an arm which is secured to the frame of t e press and adapted to be actuated by the aforementioned cam to oscillate said arm of the cam actuated ire means at pie-determined times, to position the arm. beyond but adjacent to the j ressure elements at both ends of its throw, the arm of said cam actuated means being adapted to be adjusted to vary the throw and vertical position of the arm and adjusting it to assume different relative positions with respect to the pressure elements at each end of its to and fro movement.

5. In a safety device for machines l1aving co-operating pressure elements, a disk provided with a cam face mounted for retation on the frame of the machine, a media-=- nism comprising a pivoted bracket adapted to contact with said cam, a link mechanism and a pivoted plate which is also provided with an arm which arm is adapted when actuated by said cam to oscillate to and fro between the pressure elements to a position free from the pressure elements at both ends of its throw but adjacent thereto.

6. In a safety device for machines having co-operating pressure elements, a rotary shaft, a cam mounted thereon, a pivoted bracket mounted on the frame and provided with a roller which is adapted to contact with the cam, a second bracket fixedly mounted on the frame in spaced relation to the pivoted bracket, a plate pivoted to the fixed bracket, a link connected to the pivoted bracket and plate, an arm adjustably secured to the pivot/ed plate, the arm and the link being connected to the pivoted plate in such a manner as to provide means of varying the throw of the arm.

7. In a safety device for machines having cooperating pressure elements, a rotary a second bracket fixedly mounted in spaced relation to the pivoted bracket, a plate pivoted to the fixed bracket, a link connected to the pivoted bracket and plate, an arm adjustably secured to the pivoted plate, the arm of the link being connected to the pivoted plate in such a manner as to provide means for changing the throw of the arm and its position at the end of its travel and means to adjust the end of the arm verti' an 8. In a safety device for a machine equipped with pressure elements, a rotary shaft journaled on the frame of the machine, a cam secured thereto, means pivoted to the frame carrying a roller and so located thereon as to permit the roller to be yieldingly brought in contact with the cam, a

plate pivoted to the frame in spaced relation to the pivoted bracket, a link connected to the pivoted plate and bracket and an arm secured to, the pivoted plate.

9. All of the elements defined in claim 8 characterized by the combination and construction of said parts so as to provide means for adjusting the position of the arm relative to the pressure element at the end of its stroke carrying the stroke of the arm and for vertical adjustment of the end of the arm.

In testimony whereof I affix my signature.

SIEGJFRIED SI-IOLD. 

